1. Field of Invention
The present invention relates to a broadcast receiver. More particularly, the present invention relates to a broadcast receiver dynamically adapted for different quality of the input signal.
2. Description of Related Art
For a conventional broadcast receiver having a tuner, there is usually a take over point (TOP) value pre-defined in the tuner, at which a radio frequency amplitude gain control (RF AGC) is activated in place of an intermediate frequency amplitude gain control (IF AGC). The TOP value is allocated with respect to the gain variation or performance of the tuner. For example, if the TOP value is too large, the output signal of the tuner will be influenced due to a small IF amplitude gain; on the contrary, if the TOP value is too small, the output signal of the tuner will be saturated due to a large IF amplitude gain. Alternatively, the take over point (TOP) value may be pre-defined in the tuner, at which an intermediate frequency amplitude gain control (IF AGC) is activated in place of a radio frequency amplitude gain control (RF AGC), in this case, the output of the tuner also could be influenced due to a large or small TOP value, thus affecting the following signal processing. Therefore, it is essential to properly set the TOP value according to the input signal of the tuner.